[ Upstream commit 70499cdfeb ]
Before this patch, some functions started transactions then they called
gfs2_block_zero_range. However, gfs2_block_zero_range, like writes, can
start transactions, which results in a recursive transaction error.
For example:
do_shrink
trunc_start
gfs2_trans_begin <------------------------------------------------
gfs2_block_zero_range
iomap_zero_range(inode, from, length, NULL, &gfs2_iomap_ops);
iomap_apply ... iomap_zero_range_actor
iomap_begin
gfs2_iomap_begin
gfs2_iomap_begin_write
actor (iomap_zero_range_actor)
iomap_zero
iomap_write_begin
gfs2_iomap_page_prepare
gfs2_trans_begin <------------------------
This patch reorders the callers of gfs2_block_zero_range so that they
only start their transactions after the call. It also adds a BUG_ON to
ensure this doesn't happen again.
Fixes: 2257e468a6 ("gfs2: implement gfs2_block_zero_range using iomap_zero_range")
Cc: stable@vger.kernel.org # v5.5+
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
888d9b829c